Thermal controller for incubators



1",61'6,307 J. E. DAVIS THERMAL CONTROLLER FOR INCUBATORS Feb. 1, 1927.

' Original Filed Nov. 20, 1922 {i iz Patented Feb. 1, 1927.

JESSE E. DAVIS, OF CAMBRIDGE, IOVA.

' THERMAL CONTROLLER FOR INCUBATORS.

Application filed November 20, 1922, Serial 1T0. 602.175. Renewed May 24, 1926.

The object of my invention is to provide a thermal controller adapted for use with an incubator or the like, and having parts so arranged and constructed that an alarm will be actuatedwhen the heat in the incubator reaches a certain minimum or a certain "maximum temperature.

A further objectv is to provide such a device,- having means, whereby in case of fire an alarm will be sounded. QWith these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my device, whereby the objects contemplated are'attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

Figure 1 shows 'a perspective view of part of an incubator equipped with my improved alarm device.

' Figure 2 shows aside elevation of the operative mechanism of the alarm device.

Figure 3 shows a horizontal, sectional view taken on theline 3-3 of Figure 2.

Figure 4 shows a detail, sectional view taken on the line 44 of Figure 3; and

@Figure 5 shows a vertical, sectional view through part of the mechanism, taken on the line 5'5 of Figure 2;

In the accompanying drawings, I have used the reference numeral to indicate generally .the body ofan incubator having on its interior the'heating chimney 11.

My improved alarm device comprises a switch structure and means for actuating saidswitch structure according to the condition of the incubator thermostat. It ineludes also means for actuating the switch structure m-case a fire occurs, by severing an element easily destroyed by heat for I 'mounted on a suitable portable base 11*.

ture.

thereby causing an alarm.

- It is, of course, understood that the switch a structure is included in an electric circuit,

having an alarm..

My (1672108 comprises an operative mechanism, WhlCh is preferably for the most part, On

the base 11 near one end is the switch struc- In the form of the switch structure herein illustrated, I have "provlded two upright, horizontally spaced, supporting brackets 12,

1 preferably made of fiber or other insulating 'cmaterialr- J ournaled in the upper portions of the insulating material brackets 12 is a transverse, metallic shaft 13,

On one end of the shaft 13 is screwed a nut 14 and on the other end are nuts 15 and 16. On the shaft 13 adjacent to the inner faces of the respective brackets 12 are metallic discs 17 and 18 spaced from each other. T

On the shaft 13 between the discs 17 and 18 is a spacer sleeve 19. The metallic discs 17 and 18 are provided with adjacent annular shoulders 20. A hollow drum 21 of insulating material is loosely mounted on the discs 17 and 18 between the shoulders thereof.

The discs 17 and 18 have inwardly projecting contact fingers 22 and 23.

Extended through the wall of the hollow drum 21 is a screw 24 on the inner end of which is mounted a U-shaped contact member 25 and on the outer end of which outducting wire 29. A conducting wire connects the binding post 28 with the screw 24, as shown for instance in Figures 3 and 4.

A conducting wire 31 is-mounted on the metallic shaft 13 between the nuts 15 and 16. The wire 29 is connected with one pole of a battery or series of cells or other source of electrical energy 32.

The other pole of the battery is connected by a wire 33 with an alarm device, such as the bell 34 or otherwise.

The wire 31 is also connected with the alarm device 34.

The screw 14 may be loosened and there upon the discs 17 and 18 may be rotated for adjusting the contact fingers 22 and 23 to any desired positions, whereupon the screw 14 may be tightened and the discs 17 and 18 will be held in theirthen adjusted positions.

Mounted on the base 11 and spaced from the switch structure above described is an upright supporting member 35, having a vertical opening 36 therein. An upright post 37 is received in the opening 36. The post 37 has at its upper end a bifurcated arm 38. A rod 39 is pivotally mounted between the members of the arm 38 on a pin 40 extendedthrough said members.

The rod 39 is so arranged that the longer and heavier end extends from the post 37 towards the switch structure while its shorter end projects in the opposite direction from said post.

A rod 41 has at its upper end a bifurcated arm 42, between the members of which the longer end of the rod 39 is pivoted by means of a pin 43, extending through said rod and the arm 42.

Mounted in the wall of the drum 21 is a screw bolt or the like 44, having a nut- 45 011 its inner end. At the outer end of the screw bolt 44 is a head forming a socket 46. A ball 47 is loosely received in said socket and has a stem 48 provided with an internally screw-threaded sleeve 49 into which the lower end of the rod 41 is screwed.

It will be seen that by tilting the rod 39, the rod 41 will be raised and lowered for imparting limited rotary movement to the drum 21. A rod 50 is arranged adjacent to the opposite shorter end of the rod 39 and is provided at its upper end with bifurcated arms 51 between which the rod 39 is pivoted by means of a pin 52.

The lower end of the rod 50 is adjustably connected by means of a Z-shaped fitting 53 with the thermostat 54 of the incubator. The Z-shaped fitting 53 is adjustable on the r03 50 between the nuts 55 screwed onto said r0 Mounted in the upright 35 is a short shaft 56, which is arranged at right angles to the upright rod 37. The upright rod 37 is formed with a groove 58 into which the shaft 56 projects. The shaft 56 has a flat face 57, so that the shaft 56 may be rotated to a position where the flat face 57 is opposite the upright 37, whereupon the upright- 37 may be adjusted vertically.

When the upright 37 stands in position with its groove 58 opposite the shaft 56, the shaft 56' may be rotated until it enters the groove 58, at which time it will be observed that'the flat face 57 has been turned away from the upright 37.

When the shaft 56 and the upright shaft 37 are in their last position mentioned, the shaft 56 serves to hold the upright 37 in a certain position. lVhen the upright 37 is in such position, it holds the rod 39 in proper position for the operation of the device.

The contact fingers are adjusted by ad justlnent of the discs 17 and 18 to such positions that they do not engage the contact 25 during the ordinary operation of the incubator. Said contact fingers are, however,

so adjusted that when the heat in the incubator reaches a certain predetermined minimum and the thermostat contracts to its position and condition at that minimum heat, the rod 50 will be pulled down and the rod 41 will be pulled upwardly, causing the contact 25 to move from its position shown in Figure 4, for instance, to position in contact with the finger 22 on the disc 17. Thereupon a circuit will be closed through the contacts 25 and 22, the disc 17, the shaft 13 the wire 31, the alarm 34, the wire 33, the battery, the wire 29, the post 28, the wire 30, the screw 24 and the contact 25.

The finger 23 is so set that when the heat reaches a certain predetermined maximum point, the expansion of the thermostat 54 will serve to raise the rod 50 and lower the rod 41, thus imparting such rotation to the drum 21 as will bring the contact 25 into position where it will contact with the contact fingers 23.

The circuit will then be closed through the alarm, so that the attendant can take the proper steps to prevent overheating the as It will be seen from the foregoing that my device is such when the heat in the incubator reaches a certain predetermined maximum or mininnun, the alarm is sounded, and that the parts are adjustable, so that the alarm may be sounded at different predetermined temperatures.

In connection with my device, I have provided means whereby the alarm circuit will be closed in case a fire occurs accidentally in the incubator.

On one end of the shaft is a collar 60, which may be locked in position on the shaft by means of a set screw 61. On the other end of the shaft 56. is a disc or the l ke 62 on which is a pin 63. A coil spring 64 is connected with the disc 62 and with the upright 35 in such manner as to normally hold the disc 62 in position where the flat face 57 of the shaft is opposite the groove 58 in the uprigl'it 37.

Connected with the pin 63 is a device 65 adapted to be readily destroyed by heat. The device 65 may be an ordinary piece of cord or anything that will readily burn when subjected to the heat of a fire.

When the device is ready for use, the member 65 is drawn taut and extended past the chimney 11, preferably close to such chimney and anchored for instance as at 66. Before the device 65 is anchored. the disc 62 is rotated to such position that when the device 65 is anchored, the shaft 56 will enter the groove 58 in the upright 37 for holding the upright 37 in position raised above its lower limit of movement. This is the proper positionof the upright 37 for holding the rod 39 for the operation of the parts heretofore described.

It will be observed that in case the device 65 is destroyed by fire or the like, the spring 64 will impart rotation to the shaft 56 for bringing the fiat face 57 thereof to position in register with the groove 58 in the upright.- 37, whereupon the upright 37 will drop by gravity from its position shown in Figure 5 for instance, whereby the rod 39 will be lowered for bringing the contact 25 into engagement with the finger tendant will be called to the fact that something is wrong with the incubator.

I My improved device is of inexpensive construction. It will notify the attendant when the heat in the incubator goes above or below the desired predetermined temperature and will also actuate the alarm in case of fire.

I It is well knowiithat many hatchings of eggs have been lost because the incubator becomes too cold or too warm, and it is also common knowledge that there are agood many fires that start with the incubator.

, The device is readily adjustable so as to ,permitits application to various kinds and types of incubators and so as to regulate the temperatures at which the alarm is v sounded.

I' claim as my invention: 1. In a device oft-he class ClGSC-llb(ll,. the combination of a support, an arm pivoted thereon, means for operatively connecting said arm with a heat actuated element, means for connecting said arm with a movable switch element, spaced switch elements adapted to coact with thefirst-named switch element, means, including a frangible member for holding said support in raised position, whereby when the frangible element is destroyed, said support will drop down wardly actuating saidrod for bringing the movable switch element into contact with one of said spaced switch elements.

2. In a device of the class described, a switch comprising a supporting base, insulated brackets thereon, a metallic shaft journa-led in said brackets, metallic discs loosely mounted on said shaft, a spacer sleeve on the shaft between the discs, means for frictionally locking said discs in various positions with relation to said brackets, contact fingers on said discs, a hollow insulator drum loosely mounted for rotation on said discs, a contact element on said drum, whereby when said drum is rotated in different directions the contact element is moved to engagement with the respective fingers.

3. In a device of the class described, a switch structure comprising spaced contacts, an intermediate contact capable of movement to position in engagement with either of the first contacts, an upright, a member mounted for vertical sliding movement on said upright, a transverse shaft, said last described member and said transverse shaft having coacting parts whereby in one position of the shaft said parts engage for holding said member and in another position of the transverse shaft said parts clear for permitting said member to drop by gravity, a spring for normally holding the shaft and the member in their last-described positions, and a frangible member operatively connected with said shaft and adapted to hold the shaft in position for engagement with said member, and means including an element pivoted on said upright for operatively connecting said movable contact with a heat actuated element.

Des Moines, Iowa, October 20, 1922.

JESSE E. DAVIS. 

